Chained flashlight system

ABSTRACT

A chained flashlight system includes multiple flashlights; multiple lighting control devices that control lighting of the flashlights, respectively; a communication wire; and a traffic control device. The lighting control devices include receiving units, controlling units, and power supply units, respectively and are coupled to the traffic control device by the same communication wire. The traffic control device simultaneously sends a lighting signal to the lighting control devices via the communication wire. The receiving units of the lighting control devices receive the lighting signal. The controlling units of the lighting control devices turn ON the power supply units, respectively, on the basis of the time condition from reception of the lighting signal to turning ON of the power supply units, set for the respective flashlights. The flashlights are lit by turning ON the respective power supply units of the lighting control devices.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a National Stage of International Application No. PCT/JP2017/041479 filed Nov. 17, 2017, claiming priority based on Japanese Patent Application No. 2017-012997 filed Jan. 27, 2017, and the entire disclosure of which is incorporated herein its entirety by reference.

TECHNICAL FIELD

The present invention relates to a chained flashlight system.

BACKGROUND ART

In the existing chained flashlight systems used in Japanese airports, for example, 29 flashlights (hereinafter also referred to as “lamps”) are repeatedly lit sequentially from one end of a runway to the other end for about 17 milliseconds per one lamp (0.5 seconds per one cycle), and a lighting signal is directly sent from the traffic control apparatus (traffic control device) to each lamp. Therefore, many communication wires are used between the apparatus and each lamp.

As a method of reducing the number of communication wires, for example, it is conceivable to use an optical fiber, but it is difficult to newly introduce an expensive optical fiber into an airport, and the optical fiber cannot be easily attached to and detached from a flashlight requiring high waterproofness, has poor ease of handling, and involves a high maintenance cost (Patent Literature 1).

CITATION LIST Patent Literature

Patent Literature 1: JP H10-181695 A

SUMMARY OF INVENTION Technical Problem

Hence, it is an object of the present invention to provide a chained flashlight system which can reduce the number of existing communication wires while using some of the communication wires.

Solution to Problem

In order to achieve the aforementioned object, according to the present invention, there is provided a chained flashlight system which includes: multiple flashlights; multiple lighting control devices that control lighting of the respective flashlights, a communication wire; and a traffic control device. In the chained flashlight system, each lighting control device comprises: a receiving unit, a controlling unit, and a power supply unit. The lighting control devices are coupled to the traffic control device by the same communication wire. The traffic control device simultaneously sends a lighting signal to the lighting control devices via the communication wire. The receiving unit of each lighting control device receives the lighting signal. The controlling unit of each lighting control device turns ON the corresponding power supply unit on the basis of a time condition from reception of the lighting signal to turning ON of the power supply device, set for the corresponding flashlight. Each flashlight is lit by turning ON the corresponding power supply unit of each lighting control device.

Advantageous Effects of Invention

The present invention can provide a chained flashlight system which can reduce the number of existing communication wires while using some of the communication wires.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating an example configuration of the chained flashlight system according to the first embodiment.

FIG. 2 is a block diagram illustrating an example configuration of the chained flashlight system according to the second embodiment.

DESCRIPTION OF EMBODIMENTS

The chained flashlight system of the present invention is configured such that, for example, the communication wire is a bidirectionally communicable communication wire that can send a lighting signal from the traffic control device to the lighting control devices and can feed information back from the lighting control devices to the traffic control device, and the lighting control devices are coupled to the traffic control device by the communication wire.

The chained flashlight system of the present invention is configured such that, for example, it further includes a power supply device and a power supply wire, and the lighting control devices are coupled to the power supply device by the same power supply wire. The power supply wire is of preferably a single-phase two-wire type.

The chained flashlight system of the present invention is configured such that, for example, flashlights are LED flashlights.

The chained flashlight system of the present invention is configured such that, for example, the traffic control device further simultaneously sends a luminous intensity designation signal to the lighting control devices via the communication wire, the receiving unit of each lighting control device receives the luminous intensity designation signal, the controlling unit of each lighting control device turns ON the corresponding power supply unit such that luminous intensity of the corresponding flashlight during an ON-state of the power supply unit becomes luminous intensity designated by the luminous intensity designation signal, and each flashlight is lit so as to have luminous intensity designated by the luminous intensity designation signal by turning ON the corresponding power supply unit of each lighting control device.

The chained flashlight system of the present invention is configured such that, for example, each lighting control device further includes an abnormality sensing unit, the abnormality sensing unit of each lighting control device detects an abnormality of at least one unit selected from the group consisting of the corresponding flashlight, the corresponding receiving unit, the corresponding controlling unit, and the corresponding power supply unit and sends an abnormal signal to the traffic control device via the communication wire.

The chained flashlight system of the present invention is configured such that, for example, each flashlight further includes a heater; the chained flashlight system further includes heater control devices that control heating of the respective flashlights, each heater control device includes: a heater receiving unit, a heater controlling unit, and a heater power supply unit, the lighting control devices are coupled to the traffic control device by the same communication wire, the traffic control device simultaneously sends a heating signal to the heater control devices via the communication wire, the heater receiving unit of each heater control device receives the heating signal, the heater controlling unit of each heater control device turns ON the corresponding heater power supply unit, and the heater of each flashlight is lit by turning ON the corresponding heater power supply unit of each heater control device.

The chained flashlight system of the present invention is configured such that, for example, the traffic control device sends 1-bit information in the lighting signal for a predetermined pulse signal width. The predetermined pulse signal width is preferably 0.1 to 499.9 milliseconds.

The following describes the chained flashlight system of the present invention in details with reference to the drawings. However, the present invention is not limited to the following description. Note here that there may be cases where the same reference numerals are given to the same components in FIGS. 1 and 2 below, and descriptions thereof are omitted. Furthermore, in the drawings, for ease of description, illustration of the structures of the components may be simplified as appropriate, and the ratio of sizes of components and the like may be schematically indicated contrary to reality.

First Embodiment

FIG. 1 is a block diagram illustrating an example configuration of the chained flashlight system (hereinafter also referred to as “system”) according to the present embodiment. As shown in FIG. 1, a system 10 according to the present embodiment includes flashlights A₁ to A_(n), lighting control devices B₁ to B_(n), a communication wire C, and a traffic control device D. The lighting control devices B₁ to B_(n) include receiving units b1 ₁ to b1 _(n), controlling units b2 ₁ to b2 _(n), and power supply units b3 ₁ to b3 _(n), respectively. In the system 10 according to the present embodiment, the flashlights A₁ to A_(n) are coupled (hereinafter also referred to as “connected”) to the lighting control devices B₁ to B_(n), respectively. The lighting control devices B₁ to B_(n) are connected to the traffic control device D by the same communication wire C. Although not shown, in the system 10 according to the present embodiment, in order to guide an aircraft to a runway, the flashlights A₁ to A_(n) are arranged linearly such that the flashlight A₁ is arranged at an end on the side opposite to an approach direction for the aircraft relative to an end at an approach entrance for the aircraft in the runway, and the flashlight A_(n) is arranged at the end on the approach entrance side of the runway. In FIG. 1, an arrow AD indicates an approach direction for the aircraft.

The flashlights A₁ to A_(n) may be any lamp capable of emitting flashes, and known flashlights can be used. Specific examples thereof include as xenon light (xenon flashlight), an LED light (LED flashlight), and the like, and the LED light is preferable because it can reduce power consumption. The number n of sets based on one set of a flashlight and a lighting control device corresponding to the flashlight in the system 10 according to the present embodiment is an integer of three or more. However, the number n of the sets may be an integer of two or more and can be set, as appropriate, according to the number of sets of flashlights in the chained flashlights, defined in each country, for example. Specifically, the number n of the sets is, for example, 2 to 30, and is, for example, 29 in Japan. Moreover, in each set, the number of flashlights A_(n) connected to the lighting control device B_(n) is not particularly limited and is, for example, one. The flashlights A₁ to A_(n) may have address information Ia_(n) which can identify the flashlights A₁ to A_(n), for example.

The lighting control devices B₁ to B_(n) control lighting of the flashlights A₁ to A_(n), respectively. In the system 10 according to the present embodiment, the lighting control devices B₁ to B_(n) have the receiving units b1 ₁ to b1 _(n), the controlling units b2 ₁ to b2 _(n), and the power supply units b3 ₁ to b3 _(n), respectively and may further include other units, specifically the respective abnormality sensing units to be described below. The lighting control devices B₁ to B_(n) may have address information Ib_(n) which can identify the lighting control devices B₁ to B_(n), for example.

The receiving units b1 ₁ to b1 _(n) receive a lighting signal. As each of the receiving units b1 ₁ to b1 _(n), a receiver capable of receiving an analog signal or a digital signal according to the type of the signal sent by the traffic control device D can be used, and specific examples of the receiver include an analog signal receiver and a digital signal receiver. When the receiving units b1 ₁ to b1 _(n) are analog signal receivers, they preferably include the respective digital-to-analog converters. The receiving units b1 ₁ to b1 _(n) may further have a sending function of being capable of sending information and the like on the lighting control devices B₁ to B_(n). In this case, the receiving units b1 ₁ to b1 _(n) can also be referred to as, for example, sending/receiving units. The information can be, for example, an abnormal signal to be described below. When the receiving units b1 ₁ to b1 _(n) have a sending function and send the information to the traffic control device D by the analog signal, they preferably include the respective digital-to-analog converters. The lighting signal is, for example, a signal for instructing the flashlights A₁ to A_(n) to emit flashes. If the flashlights A₁ to A_(n) are lamps, such as LED lights or the like, that continue to be lit once they are lit, the lighting signal preferably includes at least one of a signal relating to the lighting time of the flashlights A₁ to A_(n) or an extinguishing signal for turning OFF the flashlights A₁ to A_(n) after the elapse of the lighting time. The lighting time is, for example, 0.01 to 50 milliseconds.

The controlling units b2 ₁ to b2 _(n) turn ON the power supply units b3 ₁ to b3 _(n), respectively, on the basis of the time condition from the reception of the lighting signal to the turning ON of the power supply units b3 ₁ to b3 _(n), set for the respective flashlights A₁ to A_(n). The controlling units b2 ₁ to b2 _(n) may be any devices capable of turning ON the power supply units b3 ₁ to b3 _(n), respectively, and examples thereof include a CPU (Central Processing Unit), a microprocessor, and a microcontroller. The time condition may be a time condition where the flashlights A₁ to A_(n) are lit sequentially at a predetermined time interval T_(p) in order from the flashlight A₁ to the flashlight A_(n). As a specific example, the time condition for the controlling unit b2 _(n) is a time condition where the power supply unit b3 _(n) is turned ON after the elapse of T_(p)×n seconds from the reception of the lighting signal. The predetermined time interval T_(p) is, for example, about 17 milliseconds. The predetermined time interval T_(p) may be set considering a time lag T occurring until the lighting control devices B₁ to B_(n) receive the lighting signal sent simultaneously, for example. If the flashlights A₁ to A_(n) are LED lights, and the lighting signal includes at least one of a signal relating to the lighting time of the flashlights A₁ to A_(n) or an extinguishing signal for turning OFF the flashlights A₁ to A_(n) after the elapse of the lighting time, the controlling units b2 ₁ to b2 _(n) preferably turn OFF the power supply units b3 ₁ to b3 _(n) on the basis of the signal relating to the lighting time or the extinguishing signal.

The flashlights A₁ to A_(n) are lit by turning ON the power supply units b3 ₁ to b3 _(n). The power supply units b3 ₁ to b3 _(n) may be any means capable of lighting the respective flashlights A₁ to A_(n), and known voltage-applying means may be used, for example. When the flashlights A₁ to A_(n) are xenon lights, the power supply units b3 ₁ to b3 _(n) preferably further send a trigger signal for causing the flashlights A₁ to A_(n) to emit light. The power supply units b3 ₁ to b3 _(n) may further include the respective known electric accumulation means such as condensers (capacitors), for example. When the power supply units b3 ₁ to b3 _(n) include the respective electric accumulation means, the power supply units b3 ₁ to b3 _(n) turn ON the respective flashlights A₁ to A_(n) by supplying electric power in the electric accumulation means to the respective flashlights A₁ to A_(n), for example.

The communication wire C may be any communication wire capable of performing data communication, and a known communication wire can be used. Specific examples of the communication wire C include a metal communication cable and an optical fiber communication cable. The communication wire C is preferably a metal communication cable because it is easy to attach and detach. In the system 10 according to the present embodiment, the communication wire C is connected to the lighting control devices B₁ to B_(n) in bus topology because it is easy to use the existing communication wire C, for example. However, the communication wire C may be connected to the lighting control devices B₁ to B_(n), for example, in series as long as each of the lighting control devices B₁ to B_(n) and the traffic control device C are connected to each other by the same communication wire C, i.e., a common communication wire C. In the system 10 according to the present embodiment, the communication wire C functions as a communication wire for sending a lighting signal from the traffic control device D to the lighting control devices B₁ to B_(n). Therefore, the communication wire C can also be referred to as an input communication wire, for example. The number of communication wires C is not particularly limited and may be, for example, one or two or more. In the latter case, one of the two or more communication wires may be used as an input communication wire, and the other one may be used as an output communication wire for feeding information back from the lighting control devices B₁ to B_(n) to the traffic control device D. In this case, for example, one communication wire C may serve as both of the input communication wire and the output communication wire. In this case, the communication wire C may be, for example, a bidirectionally communicable communication wire.

The traffic control device D simultaneously sends a lighting signal to the lighting control devices B₁ to B_(n) via the communication wire C. The traffic control device D may be a device capable of generating the lighting signal and can be, for example, a CPU, a microprocessor, or a microcontroller.

Next, a method for lighting the flashlights A₁ to A_(n) using the system 10 according to the present embodiment will be described.

First, the traffic control device D simultaneously sends a lighting signal to the lighting control devices B₁ to B_(n) via the communication wire C. The number of times of sending the lighting signal from the traffic control device D may be one or multiple times, and however, the latter is preferable. In the latter case, it is preferable that the traffic control device D repeatedly sends the lighting signal for a time period designated by a user, such as an air traffic controller, at a predetermined time interval T_(f), for example. The predetermined time interval T_(f) is, for example, about 500 milliseconds.

Next, the receiving units b1 ₁ to b1 _(n) of the lighting control devices B₁ to B_(n) receive the lighting signal sent by the traffic control device D. When the receiving units b1 ₁ to b1 _(n) receive the lighting signal, the controlling units b2 ₁ to b2 _(n) turn ON the power supply units b3 ₁ to b3 _(n), respectively, on the basis of the time condition from the reception of the lighting signal to the turning ON of the power supply units b3 ₁ to b3 _(n), set for the respective flashlights A₁ to A_(n). The flashlights A₁ to A_(n) are lit by turning ON the respective power supply units b3 ₁ to b3 _(n). As a specific example, the time condition for the controlling unit b2 _(n) is a time condition where the power supply unit b3 _(n) is turned ON after the elapse of T_(p)×n seconds from the reception of the lighting signal. When the predetermined time interval T_(p) is about 17 milliseconds, the flashlights A₁, A₂, [ . . . ], A_(n) are lit after about 17 milliseconds, about 34 milliseconds, [ . . . ], about 17×n milliseconds from the reception of the lighting signal, respectively. The flashlights A₁ to A_(n) are arranged linearly such that the flashlight A₁ is arranged at an end on the side opposite to an approach direction for the aircraft relative to an end at an approach entrance for the aircraft in the runway, and the flashlight A_(n) is arranged at the end on the approach entrance side of the runway. Therefore, in the case where a pilot of the aircraft sees the flashlights A₁ to A_(n), the flashlights A₁ to A_(n) are lit sequentially at a time interval of about 17 milliseconds along an approach direction for the aircraft (an direction indicated by the arrow AD).

As described above, in the system 10 according to the present embodiment, flashlights A₁ to A_(n) are lit after the reception of the lighting signal sent by the traffic control device D on the basis of the time condition for the controlling units b2 ₁ to b2 _(n) of the lighting control devices B₁ to B_(n). In the existing chained flashlight system, a communication wire is provided for each lighting control device to individually send a lighting signal to each lighting control device by the traffic control device. However, the system 10 according to the present embodiment is not required to provide a communication wire for each lighting control device, and a communication wire thus can be provided at low cost. In addition, the system 10 according to the present embodiment can reduce the number of existing communication wires to, for example, one while using the existing communication wire, by connecting one of the existing communication wires to all the lighting control devices B₁ to B_(n), for example.

The system 10 according to the present embodiment may include, for example, a pair of communication wires. In this case, in the system 10 according to the present embodiment, the communication wires are bidirectionally communicable wires that can send a lighting signal from the traffic control device to the lighting control devices and can feed information back from the lighting control devices to the traffic control device, and the lighting control devices are preferably coupled to the traffic control device. The lighting control devices are preferably coupled to the traffic control device by the same communication wire, for example. The communication wire may be, for example, a pair of communication wires. In this case, the system 10 according to the present embodiment includes a pair of communication wires, one of the communication wires is an input communication wire for sending a lighting signal from the traffic control device to the lighting control devices, and the other communication wire is an output communication wire for feeding information back from the lighting control devices to the traffic control device, and the lighting control devices are preferably coupled to the traffic control device by the same output communication wire. Between the pair of communication wires, one can also be referred to as a (+) wire, and the other can also be referred a (−) wire, for example. The input communication wire and the output communication wire can be described with reference to the description of the above-mentioned communication wire, for example. With the bidirectionally communicable communication wire or the output communication wire, information of an abnormal signal to be described below can be fed back to the traffic control device, for example. Accordingly, for example, statuses of the flashlights A₁ to A_(n) and the lighting control devices B₁ to B_(n) can be monitored, and they can be maintained at an appropriate time.

The system 10 according to the present embodiment further includes, for example, a power supply device and a power supply wire, and the lighting control devices are coupled to the power supply device by the same power supply wire. The power supply device may supply electric power to the flashlights and the lighting control devices via the power supply wire, and a known power supply can be used, for example. The power supply wire is not particularly limited, and a known electric wire can be used. The type of the power supply wire is not particularly limited, and can be determined, as appropriate, according to a power distribution system. The type can be, for example, a single-phase two-wire type, a single-phase three-wire type, or a three-phase three-wire type and is preferably a single-phase two-wire type because wiring is easy, and installation can be performed inexpensively.

The system 10 according to the present embodiment is preferably configured such that, for example, the traffic control device D simultaneously sends a luminous intensity designation signal to the lighting control devices B₁ to B_(n) via the communication wire C, the receiving units b1 ₁ to b1 _(n) of the lighting control devices B₁ to B_(n) receive the luminous intensity designation signal, the controlling units b2 ₁ to b2 _(n) of the lighting control devices B₁ to B_(n) turns ON the respective power supply units b3 ₁ to b3 _(n) such that luminous intensity of the flashlights A₁ to A_(n) during an ON-state of the respective power supply units b3 ₁ to b3 _(n) becomes luminous intensity designated by the luminous intensity designation signal, and the flashlights A₁ to A_(n) are lit so as to have luminous intensity designated by the luminous intensity designation signal by turning ON the power supply units b3 ₁ to b3 _(n) of the lighting control devices B₁ to B_(n), respectively. The luminous intensity of the flashlights A₁ to A_(n) during the ON state, designated by the luminous intensity designation signal, is, for example, a peak luminous intensity of the flashlights A₁ to A_(n) after turning ON of the power supply units b3 ₁ to b3 _(n). The luminous intensity designation signal may be, for example, a signal designating a numerical value of a specific luminous intensity or a signal designating a luminous intensity set in advance. The luminous intensity set in advance is not particularly limited and can be, for example, high lighting (e.g., 6000 to 20000 cd), medium lighting (e.g., 600 to 2000 cd), or low lighting (e.g., 100 to 450 cd). As described above, in the case where the luminous intensity designation signal is a signal designating a luminous intensity set in advance, for example, the luminous intensity may be set such that when the traffic control device D sends the lighting signal, the flashlights A₁ to A_(n) emit flashes with a luminous intensity of high lighting, and when the traffic control device D sends the luminous intensity designation signal, the flashlights A₁ to A_(n) emit flashes with a luminous intensity of medium lighting or low lighting. The system 10 according to the present embodiment can adjust the luminous intensity of the flashlights A₁ to A_(n) to be appropriate depending on the different circumstances of the ambient brightness, such as, for example, in the morning, day, evening, night, etc., by allowing the traffic control device D to send the luminous intensity designation signal. The pilot of the aircraft thus can more clearly recognize the flashes of the flashlights A₁ to A_(n).

In the system 10 according to the present embodiment, the lighting control devices B₁ to B_(n) preferably further include the respective abnormality sensing units, for example. In this case, it is preferred that the abnormality sensing units of the lighting control devices B₁ to B_(n) detect an abnormality of at least one unit selected from the group consisting of the flashlights A₁ to A_(n), the receiving units b1 ₁ to b1 _(n), the controlling units b2 ₁ to b2 _(n), and the power supply units b3 ₁ to b3 _(n) and send an abnormal signal to the traffic control device D via the communication wire. In the case where the communication wire is a pair of communication wires, the abnormality sensing units preferably send an abnormal signal to the traffic control device D via the output communication wire, for example. The abnormality sensing units can be determined, as appropriate, according to, for example, the type of the flashlights A₁ to A_(n), the receiving units b1 ₁ to b1 _(n), the controlling units b2 ₁ to b2 _(n), and the power supply units b3 ₁ to b3 _(n) and can be means for sensing voltages, currents, and the like of the respective units. Since the abnormality sensing units can easily identify a flashlight and a unit with abnormality, the address information Ia_(n) of the flashlights A₁ to A_(n) or the address information Ib_(n) of the lighting control devices B₁ to B_(n) may also be sent to the abnormality sensing units, for example. Abnormalities of the flashlights A₁ to A_(n) and each unit may be, for example, abnormalities of the flashlights A₁ to A_(n) and each unit themselves or abnormalities such as breakage of wire in the connection of the flashlights A₁ to A_(n) and each unit to other units. In the case where the number of communication wires C is one, the abnormality sensing units may send an abnormal signal via one communication wire C as a substitute for the output communication wire, for example. With the abnormality sensing units, the abnormal signal can be fed back to the traffic control device. Accordingly, for example, abnormalities of the flashlights A₁ to A_(n) and the lighting control devices B₁ to B_(n) can be monitored, and they can be maintained at an appropriate time.

In the system 10 according to the present embodiment, the flashlights A₁ to A_(n) preferably further include the respective heaters, for example. Each heater is not particularly limited, and a known heater can be used. In the case where the flashlights A₁ to A_(n) in the system 10 according to the present embodiment include the respective heaters, it is preferable that the system 10 according to the present embodiment includes heater control devices that correspond to the respective flashlights A₁ to A_(n) and controls the heaters of the respective flashlights A₁ to A_(n), and each heater control device includes a heater receiving unit, a heater controlling unit, and a heater power supply unit, the heater control devices are coupled to the traffic control device D by the same communication wire, the traffic control device D simultaneously sends a heating signal to the heater control devices via the communication wire, the heater receiving unit of each heater control device receives the heating signal, the heater controlling unit of each heater control device turns ON the corresponding heater power supply unit, and the heaters of the flashlights A₁ to A_(n) are lit by turning ON the respective heater power supply units of the heater control devices. Specific examples of the heater receiving unit, the heater controlling unit, and the heater power supply unit can be described with reference to the description of the specific examples of the receiving units b1 ₁ to b1 _(n), the controlling units b2 ₁ to b2 _(n), and the power supply units b3 ₁ to b3 _(n), for example. Any one or two or more units among the receiving units b1 ₁ to b1 _(n), the controlling units b2 ₁ to b2 _(n), and the power supply units b3 ₁ to b3 _(n) may also have a function of the heater receiving unit, the heater controlling unit, and the heater power supply unit, for example. The communication wire C may also serve as a communication wire for sending the heating signal. When the flashlights A₁ to A_(n) include the respective heaters, snow and ice on the flashlights A₁ to A_(n) can be melted in cold climate areas where snow falls or freeze occurs, for example. Therefore, for example, a reduction in luminous intensity of the flashlights A₁ to A_(n) can be prevented, and the pilot of the aircraft can more clearly recognize the flashes of the flashlights A₁ to A_(n).

In the system 10 according to the present embodiment, the traffic control device D sends 1-bit information in the lighting signal for a predetermined pulse signal width, for example. The predetermined pulse signal width is, for example, 0.1 to 499.9 milliseconds. As a specific example, the lighting signal is 256-bit information, and when the lighting signal is sent as one or more signals, the traffic control device D sends 1-bit information for the first time and thereafter sends the remaining 255-bit information by 1 bit at a predetermined time interval, for example. The predetermined time interval is, for example, 2.3 to 1.95 milliseconds. The predetermined time interval is, for example, the time required to send (n+1)th 1-bit information in the lighting signal from the time at which n-th 1-bit information of the lighting signal is sent. The predetermined time interval is preferably constant. The proportion of the signal width (pulse width) during which 1-bit information is sent at each interval is not particularly limited. The proportion is, for example, 50% to 90%. When the system 10 according to the present embodiment can designate the luminous intensity, the traffic control device D may send 1-bit information in the luminous intensity designation signal for a predetermined pulse signal width in addition to or as a substitute for the lighting signal. The system 10 according to the present embodiment includes the heaters, the traffic control device D may send 1-bit information in the heating signal for a predetermined pulse signal width in addition to or as a substitute for the lighting signal. When the system 10 according to the present embodiment includes the abnormality sensing units, the traffic control device D may receive 1-bit information in the abnormal signal sent by the abnormality sensing units for a predetermined pulse signal width. In this case, the abnormality sensing units may send 1-bit information in the abnormal signal for a predetermined pulse signal width. The predetermined pulse signal widths for the luminous intensity designation signal, the heating signal, and the abnormal signal can be described with reference to the descriptions of the predetermined pulse signal width for the lighting signal by reading the “lighting signal” as the “luminous intensity designation signal”, the “heating signal”, or the “abnormal signal”, for example. As described above, when the traffic control device D sends or receives 1-bit information in each signal for a predetermined pulse signal width, an influence of noise that may be contained in each signal by surge or the like can be reduced, for example. Therefore, the system 10 including the traffic control device D that sends or receives 1-bit information in each signal for a predetermined pulse signal width is excellent in resistance to noise and signal deterioration, for example. Accordingly, as a communication wire C, a communication wire that is not an optical fiber communication cable or a communication wire that does not include a shielding wire, i.e., an existing communication wire can be used. Furthermore, by setting the proportion of the signal width to the above-mentioned proportion, the resistance to noise can further be improved, and deterioration of each signal can further be prevented, for example.

Second Embodiment

The second embodiment is an another example of the chained flashlight system including a pair of communication wires and the abnormality sensing units. FIG. 2 shows an example configuration of a chained flashlight system 20 according to the present embodiment. As shown in FIG. 2, the system 20 according to the present embodiment is configured such that the system 10 according to the first embodiment includes a pair of communication wires C as a substitute for the communication wire C, and the pair of communication wires C includes an input communication wire C1 and an output communication wire C2, and the lighting control devices B₁ to B_(n) include abnormality sensing units b4 ₁ to b4 _(n), respectively. The lighting control devices B₁ to B_(n) are connected to the traffic control device D by the same input communication wire C1 and the same output communication wire C2. Except for this, the system 20 according to the present embodiment has the same configuration as the system 10 according to the first embodiment and can be described with reference to the description of the system 10 according to the first embodiment. In the system 20 according to the present embodiment, the abnormality sensing units b4 ₁ to b4 _(n) may detect, for example, an abnormality of at least one unit selected from the group consisting of flashlights A₁ to A_(n), the receiving units b1 ₁ to b1 _(n), the controlling units b2 ₁ to b2 _(n), and the power supply units b3 ₁ to b3 _(n) in the state before sending the lighting signal. As described above, by sensing an abnormality in the state before sending the lighting signal, flashlights A₁ to A_(n) and the lighting control devices B₁ to B_(n) can be replaced before using the flashlights A₁ to A_(n), for example. Accordingly, the system 20 according to the present embodiment can improve maintenability.

In the system 20 according to the present embodiment, the communication wires C includes the input communication wire C1 and the output communication wire C2. However, in the system 20 according to the present embodiment, the number of communication wires C may be one. In this case, the communication wire C may be, for example, a bidirectionally communicable communication wire.

The present invention has been described so far with reference to the embodiments but the present invention is not limited to the foregoing embodiments. Various modifications on the configuration and details of the present invention that are understandable by a person skilled in the art are possible within a scope of the present invention.

INDUSTRIAL APPLICABILITY

The present invention can provide a chained flashlight system which can reduce the number of existing communication wires while using some of the communication wires. Thus, the present invention is really useful in the aeronautical field, for example.

REFERENCE SIGNS LIST

-   10, 20: chained flashlight system -   A₁, A₂, A_(n): flashlight -   AD: approach direction -   B₁, B₂, and B_(n): lighting control device -   b1 ₁, b1 ₂, b1 _(n): receiving unit -   b2 ₁, b2 ₂, b2 _(n): controlling unit -   b3 ₁, b3 ₂, b3 _(n): power supply unit -   b4 ₁, b4 ₂, and b4 _(n) abnormality sensing unit -   C: communication wire -   C1: input communication wire -   C2: output communication wire -   D: traffic control device 

The invention claimed is:
 1. A chained flashlight system, comprising: multiple flashlights; multiple lighting control devices that control lighting of the respective flashlights, a communication wire; and a traffic control device, wherein each lighting control device comprises a receiving unit, a controlling unit, and a power supply unit, the lighting control devices are coupled to the traffic control device by the same communication wire, the traffic control device simultaneously sends a lighting signal to the lighting control devices via the communication wire, the receiving unit of each lighting control device receives the lighting signal, the controlling unit of each lighting control device turns ON the corresponding power supply unit on the basis of a time condition from reception of the lighting signal to turning ON of the power supply device, set for the corresponding flashlight, and each flashlight is lit by turning ON the corresponding power supply unit of each lighting control device, the communication wire is a bidirectionally communicable communication wire configured to send a lighting signal from the traffic control device to the lighting control devices and feed information back from the lighting control devices to the traffic control device, and the lighting control devices are coupled to the traffic control device by the communication wire, each lighting control device further comprises an abnormality sensing unit, and the abnormality sensing unit of each lighting control device detects an abnormality of at least one unit selected from the group consisting of the corresponding flashlight, the corresponding receiving unit, the corresponding controlling unit, and the corresponding power supply unit and sends an abnormal signal to the traffic control device via the communication wire.
 2. The chained flashlight system according to claim 1, further comprising: a power supply device and a power supply wire, wherein the lighting control devices are coupled to the power supply device by the same power supply wire.
 3. The chained flashlight system according to claim 2, wherein the power supply wire is of a single-phase two-wire type.
 4. The chained flashlight system according to claim 1, wherein the flashlights are LED flashlights.
 5. A chained flashlight system, comprising: multiple flashlights; multiple lighting control devices that control lighting of the respective flashlights, a communication wire; and a traffic control device, wherein each lighting control device comprises a receiving unit, a controlling unit, and a power supply unit, the lighting control devices are coupled to the traffic control device by the same communication wire, the traffic control device simultaneously sends a lighting signal to the lighting control devices via the communication wire, the receiving unit of each lighting control device receives the lighting signal, the controlling unit of each lighting control device turns ON the corresponding power supply unit on the basis of a time condition from reception of the lighting signal to turning ON of the power supply device, set for the corresponding flashlight, and each flashlight is lit by turning ON the corresponding power supply unit of each lighting control device, the traffic control device further simultaneously sends a luminous intensity designation signal to the lighting control devices via the communication wire, the receiving unit of each lighting control device receives the luminous intensity designation signal, the controlling unit of each lighting control device turns ON the corresponding power supply unit such that luminous intensity of the corresponding flashlight during an ON-state of the power supply unit becomes luminous intensity designated by the luminous intensity designation signal, and each flashlight is lit so as to have luminous intensity designated by the luminous intensity designation signal by turning ON the corresponding power supply unit of each lighting control device.
 6. A chained flashlight system, comprising: multiple flashlights; multiple lighting control devices that control lighting of the respective flashlights, a communication wire; and a traffic control device, wherein each lighting control device comprises a receiving unit, a controlling unit, and a power supply unit, the lighting control devices are coupled to the traffic control device by the same communication wire, the traffic control device simultaneously sends a lighting signal to the lighting control devices via the communication wire, the receiving unit of each lighting control device receives the lighting signal, the controlling unit of each lighting control device turns ON the corresponding power supply unit on the basis of a time condition from reception of the lighting signal to turning ON of the power supply device, set for the corresponding flashlight, and each flashlight is lit by turning ON the corresponding power supply unit of each lighting control device each flashlight further comprises a heater; the chained flashlight system further comprises heater control devices that control heating of the respective flashlights, each heater control device comprises a heater receiving unit, a heater controlling unit, and a heater power supply unit, the lighting control devices are coupled to the traffic control device by the same communication wire, the traffic control device simultaneously sends a heating signal to the heater control devices via the communication wire, the heater receiving unit of each heater control device receives the heating signal, the heater controlling unit of each heater control device turns ON the corresponding heater power supply unit, and the heater of each flashlight is lit by turning ON the corresponding heater power supply unit of each heater control device.
 7. The chained flashlight system according to claim 1, wherein the traffic control device sends 1-bit information in the lighting signal for a predetermined pulse signal width.
 8. The chained flashlight system according to claim 7, wherein the predetermined pulse signal width is 0.1 to 499.9 milliseconds. 